Prior eyeglass assemblies have hinges connecting the earpieces to a lens frame which are adapted to pivot the earpieces relative to the lens frame within an arc of about a 90.degree. from a folded position to an ear-engaging position. The construction of such hinges generally do not permit the earpieces to be pivoted substantially beyond the ear-engaging position without placing a dangerously high strain on the hinge components or flexing the earpieces beyond their breaking point. Strain to the eyeglass assembly is typically experienced in several common situations, such as when spreading the earpieces beyond the ear-engaging position when moving the eyeglass frame on and off a user's head, overextending the earpieces when worn on a head that is too wide for the eyeglass frame, or grabbing the earpiece by an infant. Such repeated strain to the hinge assembly will likely lead to weakening of and permanent damage to the hinge components and/or earpieces.
Some eyeglass frames include hinges which allow the earpieces to be overextended slightly beyond the ear-engaging position without placing undue strain on the eyeglass hinge assembly or earpieces. For example, U.S. Pat. No. 3,644,023 issued to Villani is directed to a spring-loaded spectacle hinge which allow the earpieces to be pivoted slightly beyond the usable or ear-engaging position. A planar stop surface 35 is provided on the earpiece to limit the further movement of the earpiece. One drawback of the prior art design is that the hinge assembly or earpiece can nevertheless be damaged if the earpiece is accidentally caused to be pivoted substantially beyond an angle where the stop surface comes into contact with the opposing surface of the eyeglass frame.
In response to the foregoing, it is an object of the present invention to provide a flexible eyeglass assembly that overcomes one or more of the above-described drawbacks and disadvantages of prior art eyeglass assemblies.